Research Article

Study on the Damage Model of Coal Rock Caused by Hydraulic Pressure and Electrical Impulse in Borehole

Figure 12

Opening degree of crack at 11 kV voltage and different hydrostatic pressures.
(a) 1 MPa hydrostatic pressure
(b) 4 MPa hydrostatic pressure
(c) 6 MPa hydrostatic pressure
(d) 8 MPa hydrostatic pressure